Blow-out mechanism



K. w. WILCKENS 2,200,108 BLOW-OUT MECHANISM Filed Aug. 10, 1958 7 YI'FFIFIIIIIIIIIIII/i;

INVENTOR ATTORNEY {Patented May7, 1940 UNITED STATES- PATENT OFFICE,

BLOW-OUT Kurt W. Wilckens, Trenton, N. J., assignor, by mesne assignments, to Heinemann Circuit Breaker Company, Trenton, N. J., a corporation of New Jersey Application August 10, 1938, Serial No. 224,036

3 Claims.

bers for effecting the suppression of the are being'mounted upon and supported by one of the breaker electrodes. Such electrode has an end 16' section forming amounting member for attach ment to a support, e. .g. the breaker casing or switch blade, and an end section having a face v forminga switchcontactor. "Intermediate such end sections the electrode is so be t as to form g a seat for, a bar having ends project ng laterally from the electrode and. having thereon arcsuppressing members. 1

Preferably the electrode is so bentas to form a magnetizing turn creating magnetic flux"on the passageof current therethrough, and the bar and 'end members are of magnetizable material, insulated from the electrode, and forming a. core and pole pieces by which the magnetic flux is concentrated and directed across the contactor face and the arc emanating therefrom so as to elongate and extinguishthearc. Between the' electrode and pole pieces there may be mounted on the bar shields of hard fibre or the like from which non-ionized particles or gases are volatilized by the arc and aid in-the suppression thereof. ese shields also provide a thermally insulating housing pro tecting'the pole pieces and breaker housing from the deleterious effects of the arc. v r

. While it is preferable toprovide both magnetic pole'pieces an'd fibre shields qn the ends of the electrode supported bar, either may be used advantageously without the other. The electrode is apertured and bentto form 45 a closed loop with one end projecting through the aperture and its two ends diverging from one another to form respectivelythe mounting membar and contactor. Preferably the suppressor bar is seated within the closed loop. 50 The characteristics and advantages of my improvementswill further appear from the following description and the accompanying drawing in illustration thereofa I I n the drawing, Fig. 1 is a longitudinal, verti- 55 cal, sectional view through a circuit breaker emliberating flbre, and have also mounted thereon bodying my improvements; Fig. 2 is-an enlarged detached side elevation of the blow-out assembly shown in Fig. 1;-Fig. 3 is a front elevation of the blow-out assembly shown in Fig. 2; Fig.

' 4 is a fragmentary'perspective view of thefixed 5 electrode and suppressing mechanism shown in Figs. 1 to 3; and Fig. 5 is a fragmentary longitudinal view of a modified construction having .the blow-out assembly mounted on the movable switch blade. In the embodiment of my invention illustrated in Figs. 1 to 4 of the drawing; a flat strip of conducting-metal has a section bent to substantially V-shape with the legs I and 2 diverging frqmthe crotch 3. A strip section 4 contains an aperture 5 for the passage of'the leg I and forms with the leg 2 a closed loop. The end of the section 4 below the aperture 5 forms a mounting member 6, extending across one end of the aperture, and containing a threaded re- 1 cess I for the engagement of a threaded mounting screw 8 which passes through aiead-in strip 9 and the casing 10.

A magnetizable core, such as-the bar of soft iron II, is encased in a fibre insulating strip l2 and mounted in and supported by the loop formed by the. stripsections 2 and l. The ends of the core ll have mounted thereon and support a housing or shield ll, preferably formed of gasand support the blow-out plates ll of magnetizable material.

The outer face of the leg I forms a contactor for the engagement of an electrode i5 mounted upon the spring pressed switch blade l6 fulcrumed on the pivot H. The switch blade may be operated through the toggle i8 by a-handle l9 and electro-magneti'c mechanism 20. Such bladeoperating mechanism, however, forms no par-t of my .present invention. I 40 The blow-opt mechanism is readily assembled as a unit by seating the-core II in the crotch formed by the legs! and 2 and mounting the fibre shield i3 and blow-out plates I] on the ends of the core, which maybe upset so as to rivet all the parts together. The unitary assemblythus provided maybe mounted as a unit in the circuit breaker casing by means of a single screw 8, with its elbow extending toward the pivot I! of'the switch blade. I

The passage of electric current through the conductors 9, 8, 8;, 4, 29nd i creates lines of magnetic force which are concentrated in the core II and pole pieces I4 and are directed across the air gap between the pole plates l4 so as to r create a magnetic field containing the contactor face of the leg I. When the electrode 15 is disengaged from such contactor face, any resulting arc is blown upward by the magnetic flux away from the fulcrum of the lever l1. Ji'he arc is thereby elongated and extinguished by being moved away from any incandescent spot to a cool surface of the electrode and is caused to impinge against the fibre shield to liberate gas tending to suppress the arc.

In the embodiment of the invention illustrated in Fig. 5, a bent electrode and associated arc suppressing mechanism such as described in connection with Figs. 1 to 4, is mounted upon the movable blade l6 to coact with a fixed electrode The projecting end section, which forms a switch contactor, forms an angle of more than degrees with the otherend section of the strip, so that a maximum of magnetic flux is created with a minimum length of strip.

The aperture in the strip is of slightly greater width than the width of the tongue projecting therethrough to form the switch contactor, and such tongue is likewise spaced from the transverse edges 01 the aperture above and below such tongue. The strips on either side of the tongue section projecting through the aperture are held against deflection into contact with such section by the metal forming the edges above and below the tongue and the rigidity of the metal is sumcient to prevent the deflection of the tongue into contact with; the upper or lower edges.

Having described my invention, I claim-- 1. In a blow-out mechanism, an electrode comprising a strip containing an aperture, said strip having a section extending across one side of said aperture and providing a mounting member, said strip having an end section looped through said aperture and having an outer face providing a switch contactor.

2. In a blow-out mechanism, an electrode comprising a conducting strip containing an aperture, said strip being bent to form a loop with an end section projecting through said aperture, said end section having a face forming a switch contactor, said strip also having a section forming a mounting member connected with strip sections on opposite sides of said aperture, a core seated in and supported by said loop, and pole pieces fixed to the end of said core and extending transversely thereto past said contactor face.

3. In apparatus of the character described, a strip of metal substantially undeformable under the impact of a switch blade and containing an aperture completely surrounded by metal, said 

